(a) Field of the Invention PA1 (b) Description of Prior Art
The present invention relates to an iron-type golf club head such as an iron, sand wedge or pitching golf club head.
For this kind of golf club head, there is proposed a golf club head disclosed in Japanese U.M.Appln Laid-Open No.60-177867, which discloses in FIG. 2, a golf club head having multiple cavities at its back. The prior golf club head aimed at decreasing air resistance when swinging the same by forming multiple cavities at the back of the head body which had been conventionally formed smooth. Further, there is also proposed another golf club head disclosed in Japanese Patent Appln Laid-Open No.2-241469, which discloses in FIG. 1, a wood-type golf club head having small cavities formed along a peripheral portion of the head body by cutting process. According to the latter prior golf club head, the said small cavities could enchance a sense of beauty.
Whereas, it is widely recognized that for enlargement of so-called sweet area, iron-type golf club head (hereinafter called head) should have an elongated distance between the CG of the head body and the face, or otherwise, should have the weight distribution dispersed toward the periphery thereof by thickening an edge of the face. However, according to the prior golf club heads, the face must be formed to a preset thickness because of requirement for the strength at the time of striking balls, therefore, a predetermined weight would be inevitably required for the ensuring of the thickness of the face. As a result, there has been a problem such that a golf club head can not be formed as you like.